It is proposed to conduct a mechanistic study on the hydrogen-transfer step of the NAD(P)ion-dependent dehydrogenase reactions in the enzymatic as well as in vitro model systems, in the hope of obtaining evidence for radical intermediates. The approach to be employed is utilization of the extremely rapid radical rearrangments and isomerizations as probe for the possible radical intermediacy. The objectives of the proposed research are a) preparation and chemical study of a variety of the carbonyl componds which are capable of such rapid radical rearrangements, and b) their utilization in the enzymatic and in vitro model reactions of NAD(P)ion-dependent dehydrogenase activity.